Retaining means for punches



March 28, 1939. "c. F MAUTE 2,152,072

RETAINING MEANS FOR PUNCHES Filed July 15, 1938 *wA/l/ Innken'zoz;

Patented Mar. 28, 1939 UNHTE STA PATENT OFFICE 5 Claims.

This invention relates generally to tool holders but more particularly to improved means for retaining interchangeable punches in their holders or punch-supporting blocks.

It has for one of its objects to provide a retaining means of this character which is so designed and constructed as to effectually and positively retain the punch in the holder and permit of the installation and removal of the punch in a minimum period of time.

Another object of the invention is the provision of a punch retaining means which is simple and inexpensive in construction.

Other features of the invention reside in the construction and arrangement of parts hereinafter described and particularly pointed out in the appended claims.

In the accompanying drawing:

Figure 1 is a perspective View of a punchblock assembly equipped with my improved retaining means. Figure 2 is an enlarged fragmentary transverse section thereof taken on line 22, Figure 1. Figure 3 is a horizontal section taken in the plane of line 33, Figure 2.

Similar characters of reference indicate corresponding parts throughout the several views.

My improved retaining means has been designed more particularly for use in holding punches in the holders or supporting blocks of a punch press and, as shown in the drawing, the numeral iil indicates the tool-holder or supporting block adapted to be secured to the movable head of the punch press (not shown) and II indicates the punch having its shank detachably fitted in a vertical opening l2 formed substantially centrally of the block. At one side of this opening the block has a substantially key-holeshaped opening including a circular bore l3 parallel to the punch-receiving opening l2 and a vertical slot M disposed transversely between such bore and opening and in intersecting relation therewith.

The bore I3 is preferably smoothwalled and unthreaded, and removably seated therein to turn freely is a set. screw 55 which is supported therein against downward displacement by a shoulder 16 formed at the lower end of said bore and against which the lower end of the set screw is adapted to abut in the manner shown in Figure 2. In its lower end this set screw may be provided with a socket l! for receiving a suitable wrench I8 to turn it.

In its upper or shank portion the punch II has a longitudinal groove or key-way IS with which a detachable-key 20, guided in the vertical slot I4 of the tool-holder i0, is adapted to engage in the manner shown in Figures 2 and 3 for retaining the punch in place in such holder. This key fits snugly in its key-way to prevent its longitudinal displacement relative to the punch 5 and is provided at its outer longitudinal edge with a row of threads or teeth 2| disposed for meshing engagement with the threads of the set screw l5.

By this construction, when it is desired to retain the punch in the holder, the punch II and its key 20 are inserted in the companion opening l2 and slot I4, respectively, after which the set screw is screwed into interlocking engagement with the threads of the key for ef- 15 fectually and positively retaining the punch against axial and turning displacement in its holder. To remove the punch, the screw is turned in the reverse direction to effect the axial displacement of the punch and its retaining key from the holder.

I claim as my invention:

1. The combination with a tool holder having a tool therein containing a key-way, of a key applied to said holder in engagement with the tool key-way and having a row of threads in the outer edge thereof, and a screw fitted in said holder for engagement with the threads of said key.

2. The combination with a tool holder having a bore therein for receiving a tool including a key-way and having a key-hole-shaped opening at one side thereof including a bore and a slot connecting the respective bores, of a retaining means for holding the tool in the holder comprising a key engageable with the slot of said key-hole-shaped opening and at its inner edge with the key-way of the tool, the outer edge of the key having screw threads thereon, and a set screw fitted in the bore of the key-hole-shaped opening and adapted for engagement with the companion threads of said key.

3. Means for retaining a tool in a tool holder, comprising a key adapted for sliding movement in the holder axially of the tool and engageable at one of its longitudinal edges with the tool and provided at its opposite longitudinal edge with screw threads, and a set screw applied to said holder and engageable with the key-threads.

4. Means for retaining a tool in a tool holder having a tool-receiving bore and an adjoining parallel and intercommunicating key-holeshaped opening, comprising a key guided in the web portion of said opening for inerlocking engagement with the tool and having screw threads in the outer longitudinal edge thereof, and a set screw fitted in the bore portion of the key-holeshaped opening and engageable with the threads of said key.

5. Means for retaining a tool in a tool holder having a tool-receiving bore and an adjoining parallel and intercommunicating key-holeshaped opening, comprising a key guided in the Web portion of said opening for interlocking engagement with the tool and having screw threads in the outer longitudinal edge thereof, and a set screw freely fitted in the bore portion of the key-hole-shaped opening and engageable with the threads of said key, said screw-engaging bore having a shoulder at one end against which the opposing end of the screw is adapted to abut.

CARL F. MAU'IE. 

